High order harmonics generator

Abstract

A high-order harmonics generator includes a plurality of high-pass filters to block out DC signals. In one embodiment, high-pass filters are coupled to the output signals from an envelope detector and a power detector. A high-pass filter can also be coupled to the output of a multiplier that multiplies the filtered envelope signal and the filtered power signal. Additional multipliers may also be used at outputs of multipliers in a cascaded chain of multipliers for higher harmonics generation.

1. A harmonics generator, comprising:
 a power detector configured to receive an RF input signal and output a power signal; 
 an envelope detector configured to receive the RF input signal and output an envelope signal; 
 a first high-pass filter configured to receive the envelope signal and output a first signal; 
 a second high-pass filter configured to receive the power signal and output a second signal; 
 a first multiplier configured to multiply the first signal with the second signal and output a first product signal; 
 a second multiplier configured to multiply the second signal with the second signal and output a second product signal; 
 a third high-pass filter configured to receive the first product signal and output a third signal; 
 a fourth high-pass filter configured to receive the second product signal and output a fourth signal; 
 a third multiplier configured to multiply the first signal with the fourth signal and output a third product signal; 
 a fourth multiplier configured to multiply the second signal with the fourth signal and output a fourth product signal; 
 a fifth high-pass filter configured to receive the third product signal and output a fifth signal; and 
 a sixth high-pass filter configured to receive the fourth product signal and output a sixth signal. 
 
     
     
       2. The harmonies generator of  claim 1 , wherein the first, second, third, fourth, fifth, and sixth signals are used in a predistortion application. 
     
     
       3. The harmonics generator of  claim 1 , wherein the first, second, third, fourth, fifth, and sixth high-pass filters have the same cut-off frequency. 
     
     
       4. A method of generating harmonics from an input RF signal, the method comprising:
 detecting envelope information from the RF signal; 
 detecting power information from the RF signal; 
 filtering out DC components from envelope and power information to generate a first signal and a second signal; 
 multiplying the first signal with the second signal to generate a first product signal; 
 multiplying the second signal with itself to generate a second product signal; 
 filtering out DC components from the first product signal to generate a third signal; 
 filtering out DC components from the second product signal to generate a fourth signal; 
 multiplying the first signal with the fourth signal to generate a third product signal; 
 multiplying the second signal with the fourth signal to generate a fourth product signal; 
 filtering out DC components from the third product signal to generate a fifth signal: and 
 filtering out DC components from the fourth product signal to generate a sixth signal. 
 
     
     
       5. The method of  claim 4 , wherein the filtering also filters out low frequency components. 
     
     
       6. The method of  claim 4 , wherein the first and second signals are used by predistortion applications. 
     
     
       7. The method of  claim 4 , wherein the first and second signals are harmonics of the RF input signal.